I am building an energy efficient 15 unit apartment building in MA this spring. We can either go natural gas or electric. I am considering going all electric since the MA Energy Code is so stringent and the heat load will be relatively small even though there are very cold temps at times. We might even put on solar panels for the house meter.
The electric units would take up much less space and I would rather not have to put in gas at all. I am not thrilled about electric hot water heaters but understand that the newer tankless units are much better.
Any input would be appreciated.

I am building a 2 story house wood frame house(with basement) that is heated with radiant hot water system installed in the floor.

The joists have been blown in with loose fill cellulose (for both sound and to keep the heat up) and a plywood floor is on top of the joists. R5 foam board is installed on top of the plywood and the PEX tubes are installed to the foam board. They will be pouring a self leveling concrete on top of the PEX and then gluing down engineered wood floors.

I am designing a near zero energy home in climate zone 5 and working out the details for a double wall system.

There is a lot of talk about what kind of sheathing to use or not use due to the fact that the sheathing will be very cold. As I understand what I have read so far, it is recommended NOT to use OSB or foam but OK to use DensShield Gold, structural fiber board or plywood in Zone 5.

I'm building a new wood frame home with hot water baseboard heating in climate zone 6. The bathroom will have tile floors and I was thinking of using some electric resistance heat under the tile along with a baseboard hot water radiator in the bathroom. These electric systems are not inexpensive to install or operate so I am now considering simply running loops of Pex (the supply line to the bathroom radiator) between the joists to keep the tiles warm before the water in the line gets to the baseboard radiator.

With the help of this site I insulated and framed my basement (90 year old house, 8-9" concrete walls). I did 2 inches of XPS (EPS in hindsight would have been greener but I had a deal on some XPS), 2x framing with Roxul R-15 in between 2x. Rock is next and then floors.

I am about to close on a house that was built in 1972. It is in Longview, Texas. It is 2100 sq. ft. The garage was made into living space at an unknown date. Has a 3.5 ton central air unit and electric furnace for heat (inspector said that is too small and likely was in place before the garage was converted). Flex type ducting in the attic. My goal is to eventually do the entire place from top to bottom, as I can afford it, and make it cheap to heat and cool. I have several plans in mind. Insulation of the attic I think will be my first step.

I would like to know the correct way to fasten two layers of rigid foam insulation where the total thickness is 4". I am concerned that when hanging this thickness of foam it will be difficult to be sure that the siding application is secure. We will be using HardiePlank horizontal lap siding. This is a form of cement board and heavy on it's own. Any advice.
Thanks

I live in a 645 s.f. two-story home on pier and beam. It is not well insulated, not winterized and not the most precise construction. It is about 20 years old and we just purchased it a year ago. My husband and I had plans to work on it to get it better insulated and heated, but he passed away suddenly and now I am trying to think of the things he mentioned we might try.